Batteries used in MK and Transmitter are very susceptible to cold weather flying (below freezing). Expect half capacity if battery cools to 10F.
Batteries should be kept warm in an insulated box if possible.
The electronics do not care about cold, however, once the MK and transmitter have become frozen, condensation may form on the electronics when brought into a warm room. In this case, do not apply power until condensation has evaporated.
The EPP props that come standard on the MK become very brittle in cold weather and may snap off even with light contact with the ground.
Fingers quickly become numb in cold weather and control sensitivity fads with numbness.